The researchers found that some patients who received an LVAD experienced cognitive decline or poorer overall health.
There are two types of ventricular assist devices (VADs) - left ventricular assist devices (LVADs) and right ventricular assist devices (RVADs). They are battery operated, surgically implanted mechanical pumps that aid heart function and blood flow in individuals who have weakened hearts as a result of heart disease or heart failure.
LVADs are the most common type of VADs, helping the left ventricle pump blood to the aorta - the main artery that transports oxygen-rich blood from the heart to the rest of the body.
An LVAD may be fitted temporarily for patients waiting for a heart transplant or until the heart has recovered following surgery. For patients who are not eligible for a heart transplant, an LVAD may be fitted permanently as a long-term solution to aid heart function.
While there is no doubt LVADs can be crucial to prolonging and improving quality of life for end-stage heart failure patients, there is relatively little information on the health risks associated with the devices, according to the researchers of these latest studies.
1 in 4 LVAD patients experienced cognitive decline
In the first study, lead author Dr. Timothy Fendler, a research fellow at St. Luke's Mid America Heart Institute in Kansas City, MO, and colleagues investigated how LVADs affected the cognitive function of 1,173 patients.
The team found that in the year after patients received an LVAD, more than 1 in 4 experienced a noticeable decline in cognitive function.
Older LVAD patients and those whose devices were permanent were at highest risk of cognitive decline, according to the researchers.
Since patients with advanced heart failure often experience reduced blood flow to the brain, Dr. Fendler says LVADs should boost a patient's ability to think. These findings, however, suggest this may not be the case for all patients.
"The study showed that, while patients often experienced the expected result of improved cognitive abilities after receiving an LVAD, cognitive decline events were also unfortunately common," says Dr. Fendler.
He adds that these results should aid doctors in assessing the prognoses of LVAD patients, as well as informing potential LVAD patients of the cognitive decline risk associated with the device.
More than 35% of LVAD patients experienced poor overall health
In the second study, also led by Dr. Fendler, the researchers investigated the overall health of 164 patients from a single hospital for up to 1 year after receiving an LVAD.
The team found that 35.4% of these patients experienced poor overall health. Of these, 63.8% died, 29.3% reported poor quality of life, 5.2% had at least two heart failure-related hospital readmissions, and 1.7% suffered a disabling stroke.
What is more, the researchers found that patients who experienced poor overall health also had longer hospital stays related to the device placement, were more likely to have an LVAD placed permanently and had a higher number of bleeding events - a common side effect of the device - compared with patients who experienced good overall health after LVAD placement.
Commenting on the findings, Dr. Fendler says:
"These studies are important, because although LVAD therapy is a powerful, life-prolonging option that frequently improves heart failure-related quality of life in very sick end-stage heart failure patients, they may also be at risk of experiencing device-related complications that could impair their overall quality of life."
He adds that - as with the findings from the first study - the results should help doctors better inform patients of the health risks associated with LVAD in order to ensure they make the best treatment decision.
Dr. Fendler stresses, however, that although more than a third of patients experienced poor health after LVAD placement, their risk of death would have been significantly higher if they had not received the device.
In October 2014, Medical News Today reported on the creation of a new, implantable device - called the C-Pulse - that researchers believe could slow or reverse heart failure.